Does The Type Of Embolic Protection Influence Outcome In Carotid Artery Stenting?

Vikram Iyer¹, Gianmarco de Donato², Koen Deloose¹, Patrick Peeters³, Jürgen Verbist³, Alberto Cremonesi⁴, Fausto Castriota⁴, Carlo Setacci², Marc Bosiers.^1
1AZ St-Blasius, Dendermonde, Belgium; ²University of Siena, Siena, Italy; ³Imelda Hospital, Bonheiden, Belgium; ⁴Villa Maria Cecilia Hospital, Cotignola, Italy.

OBJECTIVES: The goal of this study was to review our experience with embolic protection devices (EPDs) during carotid artery stenting (CAS). Specifically we aimed to verify their clinical effectiveness and to compare clinical outcomes between specific devices and types of EPDs.

METHODS: The CAS databases at 3 participating centers were reviewed. Adverse events were defined as death, stroke (>24hrs), or TIA (<24hrs). We compared the risk of procedural and 30-day adverse events between patients treated with and without an EPD. We also compared these risks between different EPDs and between the different types of EPDs.

RESULTS: 3160 CAS procedures using 9 EPDs (see table I) were analysed. The risk of a procedural adverse event was 0.9% in protected and 2.3% in unprotected procedures (P=0.12). Compared to the most frequently used device (Filter Wire, Boston Scientific, Natick, MA, USA) there was no significant difference in the risk of procedural adverse events for any of the other EPDs. There was, however, an increased risk of 30-day adverse events with the Accunet (Guidant, Santa Clara, CA, USA) filter compared to the FilterWire (RR 2.67, CI 1.41-5.04, P=0.005). Pairwise comparison of proximal occlusion balloons to filters, distal occlusion balloons to filters, and proximal to distal occlusion balloons revealed no significant difference in the risk of procedural or 30-day adverse events. There was no significant difference in risk of procedural events between eccentric and concentric filters, however, the relative risk of eccentric compared to concentric filters at 30 days was 0.59 (unadjusted, CI 0.38-0.92, P=0.04). This difference was still apparent after adjustment for risk factors (RR 0.61, CI 0.39-0.95, P=0.06), but not after adjustment for risk factors and stent-type [(open-cell vs closed-cell) RR 0.76,CI 0.47-1.22, P=0.51].

CONCLUSIONS: The use of EPDs is associated with a low risk of procedural adverse events. We were unable to detect significant differences in risks of procedural adverse events between different devices or types of devices. We speculate that the observed differences seen at 30 days are largely attributable to differences in stent-type used.